Constructing a High-Performance Semi-interpenetrating Gel Polymer Electrolyte via In Situ Polymerization for Lithium Metal Batteries

Abstract

Solid-state lithium metal batteries (LMBs) are considered as one of the promising contenders for next-generation energy storage systems because of their high energy density and high safety performance. Since all-solid-state electrolytes are still hampered by low electrical conductivity and interfacial incompatibility, gel polymer electrolytes (GPEs) are more preferable with high ionic conductivities comparable to liquid electrolytes at room temperature and good contact with the electrodes. In this study, a highperformance composite GPE of semi-interpenetrating polymer networks, denoted as NVPH, was synthesized by in situ copolymerization of neopentyl glycol diacrylate (NPGDA) and vinyl ethylene carbonate monomers in an electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofiber matrix. NVPH shows a high ionic conductivity (2.89 × 10 −3 S cm −1 ), a high voltage resistance (up to 5.2 V), enhanced mechanical strength (13.8 MPa), and a large lithium transfer number (0.57) at room temperature. Most importantly, it also exhibits high stability to lithium metal anodes and effectively prevents lithium dendrite growth for long cycle life in LFP|NVPH|Li batteries, which will facilitate the practical application of LMBs.

Gel Polymer Electrolytes: Advancing Solid-State Batteries for High-Performance Applications

“…This reduction in electrolyte-electrode interfacial resistance effectively hinders problems such as the growth of lithium dendrites. The advantages of this method include low viscosity, easy handling, and the formation of a good interface [46]. However, the materials required for in situ polymerization are expensive.…”

In Situ-Polymerized Separator-Free Ionogel Electrolyte with Enhanced Interfacial Compatibility for Integrated Solid-State Lithium Batteries

“…Logically, developing an in situ process for the formation of GPEs is expected to be an effective solution to this issue. Some related work has been devoted to this strategy. − Lin et al utilized in situ thermal polymerization to incorporate dipentaerythritol pentaacrylate (DPPA) and 3,3,4,4,5,5,6,6,7,7,8,8-tridecafluorooctyl acrylate (TFOA) into PAN spinning porous membranes. The in situ thermal polymerization process led to improved interfacial properties, and the application of TFOA reduced the crystallinity of the GPEs.…”

“…This led to enhanced Li + transport capability, which enabled the constructed GPEs to exhibit an ionic conductivity of 2.52 × 10 –3 S cm –1 and a lithium-ion transport number of 0.61 at 30 °C. Liang et al synthesized a high-performance composite GPE with semi-interpenetrating polymer networks by the in situ copolymerization of neopentyl glycol diacrylate (NPGDA) and vinyl ethylene carbonate monomers in an electrospun poly­(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP) nanofiber matrix. The lithium batteries prepared with this composite GPE showed high stability with lithium metal anodes, and lithium dendrite formation was effectively suppressed.…”